U.S. President Joe Biden's public approval rating this month fell to its lowest level in almost two years, tying the lowest reading of his presidency in a warning sign for his reelection effort, a Reuters/Ipsos poll showed.

The four-day poll, which closed on Monday, showed just 36 per cent of Americans approve of Biden's job performance as president, down from 38 per cent in April. It was a return to the lowest approval rating of his presidency, last seen in July 2022. While this month's drop was within the poll's three percentage point margin of error, it could bode poorly for Biden as he faces off with Republican Donald Trump in the Nov. 5 presidential election.

Biden, a Democrat, has been largely tied with Trump in national polls asking voters how they will vote. But Trump has had slight leads over Biden in many polls in the states seen as most likely to determine the winner in the U.S. Electoral College.

The poll laid out Biden's weaknesses as well as a few strengths. The state of the economy was seen as the top issue, picked by 23 per cent of respondents as the most important problem facing the country. Some 21 per cent saw political extremism as the top issue and 13 per cent picked immigration.

Some 40 per cent of respondents in the poll said Trump, who was president from 2017 to 2021, had better policies for the U.S. economy, compared to 30 per cent who picked Biden, while the rest said they didn't know or didn't answer the question.

Trump had a significant edge on immigration, with 42 per cent of respondents preferring his approach to the issue, while 25 per cent picked Biden.

Biden had a modest advantage on the issue of political extremism, with 34 per cent of respondents picking the president's approach and 30 per cent saying Trump was better on the issue.

Respondents said they thought Trump had the better approach to foreign conflicts and terrorism, with 36 per cent favoring Trump in that area, compared with 29 per cent who favored Biden.

The state of the U.S. economy looms as one of the larger factors weighing on Biden's hopes of reelection.

Voters have been stung by several years of fast-rising consumer prices, though inflation has slowed considerably in recent months and the jobless rate has been below four per cent for more than two years. Biden's age, at 81, is also a concern for voters.

Also weighing on the president, a separate Reuters/Ipsos poll this month showed that many Democrats disapprove of Biden's response to Israel's war on Hamas militants. The poll published on Tuesday did not ask if Americans approve of Biden's support for Israel's war effort in Gaza, which sharply divides Democrats.

Looming over Trump, 77, are four criminal prosecutions, including a New York criminal hush money trial due to wrap up next week. Trump on Tuesday opted not to testify in the case, which involves charges he falsified business records, bringing his defense to a quick conclusion and clearing the way for jurors to begin deliberations next week. Two other pending trials are tied to his efforts to overturn his loss to Biden in the 2020 presidential election.

Trump falsely claims his 2020 election defeat resulted from fraud. He included the claim in a fiery speech shortly before hundreds of his supporters stormed the U.S. Capitol on Jan. 6, 2021. Five people died.

(Reporting by Jason Lange, editing by Deepa Babington)